Neurological Tests

NCS (Nerve Conduction Study)

NCS is a test commonly used to evaluate the function of the motor and sensory nerves of the human body. These studies are used for evaluation of paresthesias (numbness), tingling, burning and/or weakness of the arms and legs. Some common disorders which can be diagnosed by an NCS are peripheral neuropathy, carpal tunnel syndrome, ulnar neuropathy, Guillain-Barre syndrome, myasthenia gravis and spinal nerve compression.

The test involves placing an electrode (sensor) on the surface of the skin in one location, then delivering an electrical stimulus down a nerve several times with another electrode.

The responses of the nerve are recorded on a computer and will tell Dr. Pappas whether the nerve is functioning properly.

EMG (Electomyogram)

This test is used as a complement to an NCS and usually carried out on the same day. This test is a technique for evaluating and recording the electrical activity produced by skeletal muscles.

To perform the test, a small needle containing a recording electrode wire is placed through the skin into a muscle. Dr Pappas evaluates the electrical activity as the needle is inserted into a relaxed muscle and again as the muscle is contracted by the patient. The number of muscles tested depends upon the patients symptoms and the findings in each muscle.

The disorders which can be diagnosed with this test are the same as those diagnosed with NCS, with the addition of muscle disorders such as myopathy and myositis.

EEG (Electoencephalography)

This test is commonly used to help diagnose epilepsy (seizure disorders). An EEG involves the recording of electrical activity along the scalp produced by the firing of neurons within the brain. The recording is obtained by placing electrodes (sensors) on the scalp with a conductive gel or paste. Brain wave activity is recorded on a computer for about 20-30 minutes while you lie relaxed on a bed or a recliner. The technologist performing the study may use a flashing strobe light and may ask you to hyperventilate for a short while as a means of seeing if these induce any abnormalities in your brain waves.

The study will tell Dr. Pappas if there seems to be any propensity toward seizures/epilepsy. This can be determined even if you do not have a spell during the recording.

A MRI is a medical imaging technique which allows your physician to visualize detailed internal structures using a large magnet and radio frequency pulses, there is no radiation used during the MRI. The good contrast it provides between the different soft tissues of the body make it especially useful in brain imaging.

An MRA is very similar. The difference is it specifically visualizes the arteries. Because the machine uses a large magnet, it is unsafe for those with pacemakers, stimulator devices, ear implants, or other internal metal to undergo MRI or MRA testing.

During the test, the patient is positioned on a moveable exam table and is moved into a small tunnel until the part of the body being imaged is in the center of the tunnel. As the radio frequency pulses are emitted, a loud mechanical noise is heard. If ordered by Dr. Pappas, an IV contrast may be injected into an IV placed ahead of time while you lie in the scanner.